Electrical-brush connection and method of making the same.



0. E. BECKER. ELECIRICAL BRUSH CONNECTION AND METHOD OF MAKING THE SAME. APPLICATION FILED aPR. l3. I9l8.

1,288,474. laiented Dec. 24, 1916.

2 SHEETSSHEET I.

0. E. BECKER. ELECTRICAL BRUSH CONNECTION AND METHOD 6? APPLICAHDN FILED APR. I3. ISB. 1,288,474.

MAKING THE SAME.

Patented Dec. 24, 1918.

2 SHEET$-SHEET 2.

A? 4 2 U i OLIVER E. BECKER. OF

OAK PARK, ILLINOIS.

ELECTRICAL-BRUSH CONNECTION AND METHOD OF MAKING THE SAME..-

Application filed April 13, 1918.

1 0 mo whom it may concern:

Br it known that I, ()mvi-in E. Brenna, a citizen of the United States. residing at Oak Park. in the county of (ook and State of Illinois, have invented a certain new and useful Improvement in lllectrical-Brush Connections and Methods of Making the Same, of which thefollowing is a full, clear, roucise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to brushes for electrical machinery and method of and means for making the same.

More particularly my invention relates to gauze brushes, that is, brushes made of interwoven or interlaced wires, and the method of and means for attaching the leads or pigtails to the same.

As is well known 'to thoseskilled in the art, the body of the gauze brush is generally constructed by rolling on winding a sheet or strip of wire gauzeupon a-mandrel and then removingthe roll from the mandrel and pressing or rolling the gauze into suitable prismatic form. This is set out in the patent to Guttman, No. 599,781. j

The general practice of finishing'the gauze brush and attachin the lead vor igtail has heretofore consisted in dipping the a per part of the brush in tin or solder to fil the parts of the same for holding thefform of the brush and for forming a'suitabl rigid portion forthe attachment of the cad or pigtail. A hole-is then drilled into the upper part of the brush and thexlcadfo'r pigtail, which is usually made of strandedcable or woven ribbons, is then soldered-into said hole. e I have found thistobe unsatisfactory for a number of reasons. One objection is the amount of labor'involved. 4 A further objectionhasbeen due to the fact that heating of they brush may result in loosenin of the lead from the body of the brush, an at any event it may easily .re'sult in increasin the contact resistance between tholead an the bodyof the brush. A further and more frequently encountered objection isithe'tendone of the solderto be taken u by the cab e or lead by the capillary action of'thc solder upon the strands of the cable; thereby renderin the lead stifl., If the lead becomes fil ed with solder it becomes practically rigid and tends to interfere with the Specification of Letters Patent.

Patented Doc. 24, 1918.

Serial No. 228,377.

action of the brush in the holder and may easily -hc broken oii by bending.

My invention aims primarily to overcome these objections by an improved brush and lead construction and method of making the same. A further object is to provide means for practising the method of mamlfarture. According to my invention I take the brush body after it is roughly formed and com press the same into suitable shape, leaving a part of the brush body where the lead is tohe attached in a relatively loose condition. I then drive a spreading punch in the form of a pointed pin into the uncmnpressed portion to form a hole, somewhat according to thenmnner in which an and is forced into a piece of leather or fabric. The spreading'punch preferably does not form the hole by shearing or )unrhing, in the sense of driving the metal downward, but preferably spreads the fibers, and incidentally tearing the same apart laterally. This leaves an enlarged portion in the bod of the brush about the hole. The body of the brush with the hole formed in the enlarged portion may then be dipped to fill the top surface with solder so that the brush may better retain its form. This latter ste may, under certain conditions, be omitted. hereafter the lead or pigtail is inserted in the hole and the body of the brush about the hole is then crushed together upon the end of the lead or pigtail. v

The crushing of the body of the brush upon the igtail causes the individual fibers or wires of the gauze to grip the individual fibers of the lead or Pigtail very firmly. Thus the inter-mixing and interlacing of the strands of the wire or gauze on the strands of the flexible lead, forms an ideal gripping engagement for holding the pigtail or lead to the body of the brush.-

In practice I perform the operation of shapin the body of the brush and forming the ho e in the body of the brush in one operation in suitable dies in a punch press.

'A lead is then inserted by hand; The steps of closing the hole upon the lead and bringin the brush to final form is then vperformed v another die operation. Thus not onlydo provide a less ex ensive method of constructing the finishe brush, but-I provide also an improved and better article and further I provide a convenientmeans for performing certain steps of thesmethod -tised with above outlined. This method may be praclain gauze brushes or with the lubricated Erus'h described and claimed in patent to Schweitzer, No. 1,228,484.

In order to acquaint those skilled in the art with one particular manner in which the invention may be carried out, I shall now describe, with the aid of the accompanying drawings, the apparatus which I employ, the ste s which '1 perform and the structure of the rush secured thereby.

In the accompanying drawings, Figure 1 is'a. vertical sectional view taken on the line 1-1 of Fig. 2 of the die mechanism emplkiyed to form the brush;

ig. 2 is a horizontal sectional view taken on the lineZ2--2 of Fig. 1, showing certain of the parts in plan;-

Fig. 3 is a vertical section taken at right angles'to the section of- Fig. 1 on line 3-3 f ig F' ,4 is an elevational view of the finishin fie mechanism; I

ig. Bis a pers ective view of the roll of auze prior'to its urination into'rectangular orm' I Fig.6 illustrates the roll ofgauze as compressed into rectangular prismatic form,

with the holeandenlargenient formed at one corner- ,Fig. 7 iilustrates the body of the brush after the operation of dippin'gthe top of the brush in melted metal;

f Fig. S'is asectionalflview of the body of the brush showing' the manner of securing the unionbetween the. fibers ofthe gauze ani i thegstrands'of the lead; f l b d ig. is a erspective view ,0 he 0 y of the brush a ter the same has been dippled o s Fig. 10. ows the dies for corrugating thd sides of thegauze brush, and i Fig. 11' is" a rspective view of a brush withcorruga sides for strengthening the outer layer against spreading."

As previously explained, the'first step in producing a, brush lStO form a roll of gauze y 'rollin astrip or. sheet of the same upon a mandre lto'v produce a rough roll as shown This feature is old and is explained in the priorpatents above referred to. The roll of gauze 1, whicli later forms the bod'yfof the brush, is placed in the die mechanism shown iii Figs. 1, 2 and 3 and is there brought, to formand is punched by means of aspreading unch by the mechanism which will now may be given a preliminary shaping opera-' tion before. 'pliic1ng.in the die mechanism showii ix'i'FigsI'l, 2 and 3 or it maybe placed in the diemechanism in the rough. In Figs. 1, 2 and 3 I have shownthe roll 1 as having a preliminar shaping to bring it to subs tantinlly r ctangnlnr form, although as back normallyl described. ."The roll 1 above explained, it is not necessary, The roll 1 is rested against a back plate member 2, this back plate being bolted by means of the bolts or cap screws 3 upon the back frame member 4, mounted upon the main frame plate 5. The main frame plate 5 in turn is supported upon a suitable )illow block 6 of any desired weight and con 'guration. 7 v

The back plate 2 has a pair of stop members or projections, 6 and 7. Movable end die members 8 and 9, which are suitably cut out to receive the projections 6 and 7 as shown at 10 .a'nd 11, are guided between the Pl8}t6 2 and the front plate 12. The end die members 8 and 9are provided with projecting ends 13 and 14which are adapted to engage themd parts of the roll of gauze 1. At their rear ends the end die members 8 and 9 rest against the stops 15 and 16, which stops are rigidly connected to the mainframe plate 6. The retracting rods 17 and 18 are slidably mounted in the blocks 15 and 16 and at their inner ends are threaded to, or otherwise secured to the end die members 8 and 9; Suitable springs 19 10c $15 and 20 are inte sed between the the rods 17 andr,18, so that when the die members are moved inwardly to operate uponthe roll of gauze 1, they. nia be autoniatically retracted by means of tlie springs 19 and 20. 4 t I A front die member 23, guided in a suit-' able 'frame 24, is adapted to move in and press upon the front side of .the roll of gauze 1. A retracting -rod or plunger 25 and springs 26, serve to retract automatigfily the die member 23, as will be set out member-s8 and Sigrid also extends over-the disengagement of the die members by upward motion. This guiding plate- 27 estends across t e die member 23,

but is own. as broken away in the figures for. the sake of clearness. The guide plate 27 is secured on the top of thb 'front plate 12. It willrbe noted that the .die members 2,

8 and 23:11am 1- 28, 29 and 30 formed inthesame so that'theroll of gauze 1 may spread into .the same to form an enlargement. This is for the purpose of permitting the gauze tohes readto form a hole in the same for attac ing the lead as will be described halter,

The end die members 8 and 9 are adapted to befmovecl inward b the vertical cam pieces'or punches 811m 32, which are fastened in'the head member 33. The head member 33 is connected. in the end of the plun er ofthe punch prem, as is well understoo by those skilled in the art. The verticn-l'cam 'or punch members 31-32 proand 16 and the ead members 21 and 29 on i -side die members 23 to prevent accidental rided with the cummingshoulders 34- and 35, these shoulders being adapted to engage the tapered surfaces 36 and 37 on the end.

die members 8 and 9 to force the same toward each other when the punch members 31 and descend.

The front die member 23 is similarly provided with a shoulder 38 adapted to be engaged by the shoulder 39 of the vertical cam or punch member 40, which is also fastened in the head member 33.

The timing of these punches issuch that the unch -10 preferably closes in its die mem )er 23 against the body 1 first. The end punches 31 and 32 then close in the end dies 8 and 9 to com mess the roll of gauze 1 into substantially nished shape and size with the exception of the enlargement formed in the recesses 28, 29 and 30, of the adjacent die members. Thereafter the roll of gauze is operated upon by a spreading punch 42, which consists of a short pointed pin fastened in the bar 43. The bar 43 is in turn secured by means of a suitable shank 44 in the head member 33. e

Theroll of gauze 1 is thus transformed into the formed brush body 45, which has an enlargement 46 to receive the metal of the gauze which is spread apart or moved laterally y the formation of the hole 47. It is to be noted that the opening 47 extends onl a short distance down into the body of t e brush and also the enlargement 46 extends down only a short way.

'Thereafter the top of the brush body is dipped in tin' or solder to unite the upper strands of the gauze, as indicated at 48 in Fig. 7. Thereafter the stranded lead or pigtail'49, the upper end of which may be attached to a suitable clip 50, is inserted .in-the opening 47 and the body of the brush withthe pigtail or lead 49 in place, is then placed in a suitable closing die 51 and is pressed by the plunger 52 to compress the material of the body of the brush upon the lead 49 and at the same time forming the brush to finished-size. It is to be noted that the gauze of thebrush may be formed with the fibers thereof running parallel with the edges of the finished brush, or may run diagonal thereto, the resulting brush being securely gripped to the lead by'the mechanicalcaction alone.

It is to be noted that the spreading punch 42 tends to spread and may break some of the fibers of the gauze and when the gauze is compressed about the lead, these ends form efl'ective gripping fingers for engaging the strands ofthe lead 49 so that a secure fastening is provided.

I contemplate the use of plain gauze or lubricated gauze of the character set out in the prior patent to Schweitzer above mew tioned. a

The body of the-brush may be treated as applicationSerial set out in my co-pendinhgi arch 11th, 1918, to

Number 221,665, 'filed prevent spreadin of the layers of gauze and fraying of tEe ends. I have also discovered that the brush may be reinforced by mechanical formation, as shown in Figs. 10 and 11. punch 55, indentations or corrugations 56 may be formed in the material of the brush to provide mechanical reinforcing ribs.

By means of the die 54 and the This corrugation of the sides may be secured.

at the time that the brush is fon'ned in the operations illustra'tedin Figs. 1, 2 and 3, or it may be performed in 'a closing opera tion when the material of the brush is comressed about the lead 49 as shown in I do not intend to be limited to the precise details of construction shown or de scribed and I intend that certain modifications of the order of practising the varioussteps, such as will be apparent at once to those skilled in the art, are contemplated withip the scope of the appended claims.

I c aim:

1. The method of uniting a gauze brush and closing the hole upon-the lead bypres- 5 sure.

2. Themethod of unitin a leadon the body of a gauze brush, w ich consists in thrusting a spreading punch into a portion of the brush to spread the wires of the gauze apart sufficiently to form an openlng to receirc the end of the lead, inserting the end of the lead in said openin and closing the opening upon the lead by pressure.'

v3. The method of uniting a. flexl'ble lead to the body of a gauze brush, which consists,

in thrustinga spreading 0001 into a portion of the brush to spread t 1e wires of the gauze apart sufficiently to form an opening to re:

ceive the end of the lead, fillingthe portion,

of the brush adjacent the opening with suit.-

able metal, inserting the end of the flexible lead in said 0 ening, and closing the opening upon the lea by pressure. f

4. The method of iurriting a flexible lead and the bod of a gauze brush, which con-' sists in com-pressing and dipping the body .of the brush, except that point adjacent to where the lead is to be connectedyoprming an aperture in the'b'ody of the brush wherethe end of the flexible lead in said opening formed by spreading, and crushing the material of the gauze brush upon the end of the flexible lead to form a secure connection between the two.

6. A gauze brush and lead comprising a gauze body and a flexible stranded lead proect ing into said gauze body, said'lead being gripped mechanically by the gauze 7. A brush and lead comprising a metallic gauze brush body and a stranded flexible lead projecting into said body, the strands of the gauze being broken about said lead and having their end; thrust into grip ping engagement with said lead.

8. The method of unitinga. flexible lead to the body of a gauze brush whirh consists in con'iprcssing the body of the gauze brush, forming an aperture in the top of the body large enough to permit ready insertion of the end of the flexible lead, inserting the end of the lead in said aperture, compressing the body of the brush to final form and simultaneously closing the Sides of the aperture upon the lead to grip the same 50- curely.

In witness whereof, I hereunto subscribe my name this 9 day of April A.D. 1918.

OLIVER E. BECKER 

